APPLICANT'S ABSTRACT: An influenza pandemic, which could be more devastating than many other recognized infectious disease threats, could strike at any time. Because of this fact, international and United States governments are creating Pandemic Preparedness plans to be able to respond, control the spread of the virus, and reduce illness. One way of achieving these goals would be through the use of vaccines. This research will evaluate the feasibility of developing, manufacturing, and distributing a live, attenuated vaccine for strain(s) of influenza derived from avian sources, which could ultimately be tested in humans for potential use during an influenza pandemic. The research will begin to evaluate the hypothesis that vaccination with a live, attenuated vaccine based on a pandemic virus strain could become a feasible and practical way of controlling the spread of pandemic influenza. Based on cold-adaptation and genetic engineering technologies, Aviron is developing a live, attenuated intranasal vaccine for general use in the prevention of influenza. Applying these technologies to pandemic preparedness efforts by developing a vaccine candidate, along with augmenting related technical capabilities to support the feasibility of widespread vaccination, signify the potential worth of the NIH grant. Specifically, the plan is to: - Produce two Master Virus Seeds - Characterize the reassortants and evaluating them for safety - Manufacture the vaccine candidate to ensure suitability for human testing - Identify improvements to vaccine production timing - Model the methods required for rapid, efficient distribution and administration in mass immunization programs; - Draft a clinical trial protocol to establish the safety and immunogenicity.